The present invention relates to air-mixing systems of the type comprising a deflector device for distribution in an adjustable way of a flow of air coming from a main duct between two or more secondary ducts. The invention relates in particular to the field of air-mixing systems used in air-conditioning systems for motor vehicles. It is, however, of general application and can be used, for example, also in air-mixing systems for residential, commercial or industrial buildings.
The present applicant has already proposed, in the Italian patent application TO2001A000223, filed on Mar. 12, 2001 and still secret at the date of filing of the present application, an air-distributing system comprising a fluid device that enables deviation of a flow of air that passes through a main duct into a first secondary duct and a second secondary duct by exploiting the Coanda effect. The said known system has, however, only two operating conditions corresponding to the sending of the entire flow of air coming from the main duct either into the first secondary duct or into the second secondary duct.
The purpose of the present invention is to provide an air-mixing system based upon a deflector device of an analogical type, namely a device that is able to ensure continuous regulation of the amount of air that is sent into each of the two secondary ducts between a minimum value and a maximum value, preferably between a zero value and a value corresponding to the entire flow coming from the main duct.
With a view to achieving the above purpose, the subject of the invention is an air-mixing system having the characteristics indicated at the beginning of the present description and being characterized in that said deflector device is a fluid device.
In a first embodiment, the fluid deflector device comprises means for sending a control flow of air, which is adjustable, transversely and selectively from at least one of two opposite sides against the flow of air coming from the main duct so as to deviate continuously the main flow between a first condition in which the entire flow is sent to the first secondary duct and a second condition in which the entire flow coming from the main duct is sent to the second secondary duct.
In a second embodiment, the aforesaid fluid device comprises a flap for guiding the flow, which is set parallel to the flow and is designed to keep the flow coming from the main duct adherent to itself, by the Coanda effect, the said flap being mounted in such a way that is can oscillate between two end-of-travel positions, in order to vary continuously the direction of the main flow between a first condition in which it is sent entirely to the first secondary duct and a second condition in which the main flow is sent entirely to the second secondary duct.
The analogical-type fluid deflector device described above is used in an air-mixing system for regulation of the temperature of the air that is sent, for instance, to an environment which is to be air-conditioned. It may be envisaged, for example, that the entire main air flow will pass through a cooling body to be then distributed between the two secondary ducts, in one of which a heater is set, the two secondary ducts then converging into a single outlet duct set downstream of the heater. Alternatively, it is possible to provide, for example, a refrigerator in one of the two secondary ducts and a heater in the other secondary duct, the said ducts then converging into a single outlet duct in which the flow of air will have a temperature adjustable according to the flow of air passing through the first secondary duct and the flow of air passing through the second secondary duct.
Of course, the fluid device according to the invention can be applied to a wide range of possible types of air-mixing systems, without detriment to the principle underlying the present invention, namely that of applying, to an air-mixing system, a fluid deflector device of an analogical type.